Filipino Foreign Affairs Secretary Albert Del Rosario updates the media on developments in the Scarborough Shoal territorial standoff between the Philippines and China in the South China Sea during a press conference Thursday, April 26, in Pasay City, Philippines.

It is the latest in a series of unusually bold moves by the Philippines in its mounting multilayered resistance against China as it edges in on Manila’s maritime interests. Philippine officials have grilled the Chinese ambassador, proposed an elaborate dispute-resolution plan to its Southeast Asian neighbors, and bought two former US coast guard ships to help its navy to hold off China.

“The Philippines has come to the conclusion over the past couple of years that China is growing more determined to assert its claims,” says Scott Harold, associate political scientist with The RAND Corp., a US-based policy research institution. “As China has grown more determined to assert its claims, the Philippines has moved to rebuild its defense cooperative relations with the United States,” a staunch ally.

Manila’s campaign hit high gear this month after Chinese ships blocked Philippine attempts to arrest the crews of eight Chinese fishing boats near Scarborough Shoal, a coral reef 230 kilometers (143 miles) west of the main Philippine island of Luzon. But its vigilance had been rising since 2009 as resource-hungry China crept closer.

'Not just another spat'

Manila’s response to China under President Benigno Aquino III, seen as stronger than his predecessors on foreign policy, may not be just another two-way spat over the vast ocean area that has been a historical source of multilateral disputes.

It could pit China against the US, which wants to keep its historic military and economic hold on Asia, and add pressure on Beijing to enter negotiations, during which analysts say it would be humiliated by smaller countries with weaker militaries but more clearly defined claims to the sea – and stronger US backing.

The United States, former colonizer of the Philippines and a strong modern-day ally, posted 4,500 personnel to a Philippine island along the South China Sea for annual war games on April 14. Manila is also planning to buy a squadron of F-16 fighter jets from the US, Philippine media have reported.

On Wednesday China warned the Philippines not to “internationalize” the issue and force other countries to take sides.

Before 2010 the Philippines would verbally remind countries of its claim to the 220 barely populated islets across the sea, which is rich in fisheries, prime shipping lanes, and possible undersea reserves of oil or natural gas.

Its navy, with just 120 vessels, blushes against China’s navy, which has some 976 ships. And since the 1980s the overall weaker Philippine military has focused more on Muslim insurgents at home than on threats from overseas.

Then China started closing in.

China's claim

China claims the whole sea that extends from Singapore to Taiwan. Brunei, Malaysia, Taiwan, and Vietnam vie with China for claims to all or part of the sea area of 3.5 million square kilometers (1.4 million square miles).

Beijing says the Chinese navy was active in the South China Sea during the Han and Ming Dynasties hundreds of years ago. Manila cites international laws and treaties to back its claims. Vietnam was the last country to square off against China, last year using an armed oil exploration vessel to chase off Chinese fishing boats.

“A military clash in the South China Sea … may be more likely between China and Vietnam because Vietnam has more firepower, but the Philippines seems increasingly willing to stand up to China,” Ms. Glaser says.

China’s rift with the Philippines started in 2009, when the Chinese held naval exercises in the sea using “vintage World War II ships,” says Lin Chong-pin, strategic studies professor at Tamkang University in Taiwan.

“So the Philippines decided to go toward the US,” Mr. Lin says. “Washington took that as an opportunity to come back to East Asia with more deployment.”

Nervous

In 2010, the Philippines grew nervous about the international search for natural gas in the South China Sea region of Reed Bank, just 148 kilometers from the large Philippine island of Palawan. Chinese vessels have roamed the area recently as Manila prepares to award 15 exploration contracts, including one due to start this year, according to a report by the US-based think tank Council on Foreign Relations.

People in Palawan are “worried that a war could break out,” one resort owner on the tourism-intensive island says. China reportedly withdrew two law enforcement ships from the disputed shoal this week. But China has 1.3 billion people to feed, Mr. Harold notes, and “fishing stocks in its coastal waters have been depleted, which is why you’re seeing Chinese fishermen ranging farther afield into waters claimed by South Korea, Japan, and the Philippines,” he says.

On Tuesday, Mr. Aquino warned that China’s territorial claims were encroaching on the Philippines. His government proposed last year that Southeast Asian nations – excluding China – pursue joint economic development of the sea area. This month it warned against underestimating quiet claimants.

“There is no indication that the international community have acquiesced to China's so-called historical claim,” the Philippine Department of Foreign Affairs said in a statement. “Mere silence by other states to one’s claim is not acquiescence under international law.”

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